Electrical method and means for minimizing clogging of a water well



United States Patent [72] Inventors Norris E.Gunderson 2,118,669 5/1938 Grebe........................... 1717 Tudor Lane, South Bend, 47802; 2,217,857 10/1940 yc Hubert L. Keith, 313 State St., Mishawaka, 2,283,206 1942 Hayward Indiana 46544 2,625,374 1/1953 Newman [211 App]. No. 782,094 2,799,641 7/1957 Bell 1968 Primary ExaminerMarvin A. Cham ion [45] Patented Sept 1970 Assistant Examiner-Ian A. Calvert p A florney- Oltsch and Knoblock [22] Filed [54] ELECTRICAL METHOD AND MEANS FOR MINIMIZING CLOGGING OF A WATER WELL 2 Claims, 1 Drawing Fig.

ABSTRACT: A method and means for minimizing clogging of the inlet of a well wherein at least one first electrode is positioned in the ground laterally outwardly of said inlet, a second electrode is positioned at or inside said inlet, the negative terminal of a DC power source is connected to said first electrode and the positive terminal of said DC power source is connected to said second electrode, and a DC voltage is iml P. l0 s um U hr. 11 ll 2 0 5 55 l. [.l

References Cited UNITED STATES PATENTS pressed across said first and second electrodes to create an electrical current which flows from said second electrode to said first electrode.

1,372,743 Gardner....................... l66/65X SUMMARY TH INVENTION This invention relates to a method and means for minimizing clogging inand around the inlet screen of a well made in unconsolidated earth or. in and around the bore face of a well made in consolidated earth such as sandrock, where no screen is required. ltxconcerns the positioning of at least one first electrode in the earth laterally outwardly of said inlet and positioning a second electrode at or inside said inlet. The first electrode is electrically connected to the negative terminal of a DC power source and the second electrode is connected to the positive terminal of the power source. A DC voltage is impressed across said first and second electrodes and creates an electrical current which through the earth from said inlet to said first electrode.

In the process of taking water from a water well there is a tendency for the inlet'screen of the well'or the faceof the bore of a well in a consolidated earth aquifer to become clogged with particulate material deposited upontheinlet screen or I bore face of the well and in the. porous earth aquifer surrounding the well screen or well bore. it has been found that as the fluid is drawn from the surrounding subterranean earth towards the well inlet, electrical currents are naturally induced by the movement of the fluid in the earth materials. The amount of current induced has been found to be substantially proportionate to the rate of ,water flow and in the same direction. It is believedthat the naturally induced currents cause a substantial amount of particulate mineral material to electro-chemically drop out of solution and-to be deposited around the well inlet and upon the well screen or boreface causing the inlet to become so. clogged that the capacity of the well is reduced. In this invention a controlledelectrical current is introduced withinthe fluid bearingearth materials which opposes these naturally induced electrical currents and serves to reduce the amount of particulate material dropped out of solution and deposited around and upon the well screen or bore face.

it is therefore an object of this invention to provide a method and means for minimizing clogging of the inlet screen or bore face of a well by introducing within the earth around said well screen or bore facea controlled electrical current flowing away from the well inlet .to substantially neutralize or reverse the natural earth currents and reduce the rate and amount of deposit of mineral material around and upon the screen or bore face. I Y 1 lt is another object of this invention to provide a method and apparatusfor increasing the productive life of a well. 7

,Other objects'of this invention will become apparent upon a reading of the invention's description.

BRIEF DESCRIPTION OF THE DRAWING .The figure illustrated is a vertical view in section of one embodiment of this invention.

DESCRIPTION oF TII PI QEFERRED EMBODIMENT The preferred embodiment illustrated is not intended to be exhaustive or to limit the invention to the precise form disclosed.- lt is chosen and described in order to best explain the principles of the invention and its application and practical 'use to thereby enable others skilled in the art to best utilize the foundation or pad 16 may enclose the upper end part 11 of well casing 10 to serve as a support fora well pump l8. Well pump 18 includes a housing 20 which is positioned over well casing 10 and .is preferably mounted upon concrete pad 16. Housing20 includes a pump outlet conduit 22. A motor 24 is rnounted to the top of pump housing 20 and includes a vertical shaft26 whichextends downwardly through the pump housing into well casing 10. A plurality of impellers 28 are connected to the lower end of shaft 26 preferably below water level. A pump column pipe 21 is suspended from housing 20 and communicates. with outlet I 22. Pipe 21 extends vertically downwardly in well casing 10 and receives with clearance motor shaft 26 and includes an enlarged part or bowl 23 which houses pump impellers 28.Lower open end 26 of column pipe 21 preferably extends substantially belowfluid level 29 in well casing 10 and terminates above the upper edge of well screen Pump motor 24 rotates shaft26 and connected impellers 28. Fluid, such as water, is drawn by impellers 28 from earth stratum oraquifer 12 through well screen 14and is forced upwardly through column pipe 21 into pump housing 20 and outlet conduit 22. v v v U Electrode, means encircle screen l4 within earth stratum 12. Thus a plurality of electrodes 32 may be positioned in a circumferential set aboutwell casing 10 and extend vertically in the earth. Electrodes 32 are substantially equally spacedand preferably are locatedat substantially equal radial distances from well casing 10. Each electrode 32 preferably includes an electrically conductive rod 3l and an insulative coating 33 and has an upper end which projects slightlyabove ground and a lower endwhich extends to the approximate depth of well screen 14. Theinsulative coating33 at the lower end of each electrode 32 termi nates at the approximate level of the upperpart of screen 14to expose the lower end of rod 31. Alternately a conductor ring (not shown) may be buried at comparatively shallow depth, such .as 4 feet to 8 feet encircling and spaced from 5 feet tov 20 feet or more from the well casing and connected to a conductor extending to and above ground level.

An electrode 38 may be disposed within well screen 14, or the bore hole and preferably extends substantially the full length thereof. Electrode 38 may be positioned within screen 14 by suitable support members secured to the screen or it may be suspended from an insulated conductive wire 40 which has its lower end in electricalcontactwith the electrodeand its upper end attached by an insulator or non-conductive member 42 which is carried by the pump housing 20. In this embodiment well casing 10 and pump screen 14 are preferably constructed from a non-conductive material, such as plastic or fiber glassx ln the event the well screen is formed of electrically conductive material, the screen may constitute an electrode by electrical connection of conductor 40 thereto.

A DC power source 44, such asa DC battery or generator,

is electrically connected to electrodes 32 and 38 at or above ground leveLThe negative terminal of power source 44 is connected to upper ends of electrodes 32 and the positive terminal of power source 44 is connectedto wire 40 which .is electrically connected to electrode 38. Pump 18 is preferably suitablygrounded, such as by a wire 45 and a resistor 46connecting the pump housing to the negative terminal of power source 44. I I a in operation, the DC powersource 44 impresses a voltage.

across electrodes 32 and38 andcreateselectrical currents flowing through the earth from electrode 38 to electrodes 32 as indicated by the broken line arrows in the drawing. These currents oppose the fluid induced currents, indicated by solid line arrows, traveling through the fluid-bearing soil stratum towards well screen 14 or bore face. By thus counteringthese induced currents, the amount of particulate mineral materialdeposited upon the screen or bore face and within the adjacent surrounding porous earthis substantially reduced. The

spacing of the electrodes 32 from well-casing l0 and the amount of voltage of DC power source 44 are interrelated.

The electrodes 32 are preferably positioned 5 feet to 100 feet or more from the well screen 14. While the amount of voltage of DC power source 44 will vary according to the character of the fluid pumped, the resistance of the fluid-bearing earth stratum and the pumping rate of the fluid, such voltage will preferably be within the range of 5 to 50 volts. This method affords anodic protection to the well and cathodic protection to the pump.

In the event either or both well casing and well screen are formed of electrically conductive material, the positive terminal of power source 44 may be electrically connected thereto. in such embodiment, the separate inner electrode 38 is not needed.

It is to be understood that the use of an impeller pump in the described embodiment of this invention is for purposes of illustration only and that other types of pumps, such as a reciprocating pump, may be utilized with this invention. The invention may also be applied to flowing artesian wells where no pumping means is required We claim:

1. An apparatus for minimizing accumulation of particulate mineral material at a water well inlet defined at least in part by an electrically conductive reticulated screen, comprising at least one electrode positioned in the ground laterally outwardly of said inlet, a DC power source having its negative terminal electrically connected to said electrode and its positive terminal electrically connected to said screen so as to impress a voltage across said screen and said electrode and create an outwardly directed electrical current flowing from said screen to said electrode.

2. A method for minimizing accumulation of mineral material at a water well inlet having a reticulated screen of conductive material and the aquifer surrounding said inlet comprising the steps of positioning at least one electrode in the earth adjacent to but laterally outwardly spaced from said inlet, electrically connecting the negative terminal of a DC power source to said electrode and the positive terminal of said DC power source to said screen, and activating said DC power source during use of said well to impress a voltage across said electrode and screen and to create an outwardly directed electric current flowing to said electrode. 

